Visual acuity and contrast sensitivity after posterior lamellar keratoplasty

Abstract

. Purpose: It has previously been reported that patients who suffer from Fuchs’ endothelial dystrophy (Fuchs’ ED) have decreased contrast sensibility threshold. The removal of endothelial guttata by Descemet’s Stripping Automated Endothelial Keratoplasty (DSAEK) surgery has also been demonstrated to decrease intraocular light scatter and improve contrast thresholds. The purpose of this study was to compare different visual qualities in patients that had undergone DSAEK surgery in one eye while having untreated Fuchs’ dystrophy in the other eye. Methods: Thirty‐two eyes of 16 patients with bilateral Fuchs’ ED who had DSAEK surgery performed in one eye were enrolled. Visual acuity at 100% contrast and contrast sensitivity (CS) as evaluated by a modified simulation of the Freiburg Acuity and Contrast Test, was measured in both eyes of each patient. Results: Snellen visual acuity improved in treated eyes from 0.66 ± 0.35 (SD) before surgery to 0.38 ± 0.18 after surgery (log MAR units; p < 0.01). In eyes with untreated Fuchs’ dystrophy, visual acuity was 0.46 ± 0.14. In a pairwise comparison, there was no difference in Snellen visual acuity between treated and nontreated eyes (p = 0.12). Contrast sensitivity was significantly better in DSAEK‐treated eyes compared with untreated eyes. Mean log CS in DSAEK‐treated eyes was 1.06 ± 0.25 compared with a mean log CS of 0.84 ± 0.16 in untreated eyes (p < 0.01). Fourteen of 16 patients (88%) reported that vision in their DSAEK‐treated eye had the best visual quality. Conclusion: In this study, using a paired design, we demonstrate improved CS in DSAEK‐operated eyes when compared with the other eye that had untreated Fuchs’ ED despite the fact that no difference in visual quality was detected with standard Snellen visual acuity. Contrast sensitivity appears to be superior to normal visual acuity measurements in the evaluation of overall visual quality after DSAEK.

Quantitative Regional Differences in Corneal Endothelial Abnormalities in the Central and Peripheral Zones in Fuchs' Endothelial Corneal Dystrophy

“…Recent studies have shown that guttae evoke forward light scatter and cause visual impairment. 41,42 After DSAEK, forward light scatter remained greater in eyes with Fuchs' endothelial corneal dystrophy than in normal eyes and was correlated with recipient visual acuity. 41 Eyes with Fuchs' endothelial corneal dystrophy that underwent DSAEK had improved contrast sensitivity compared with other untreated eyes despite no difference in the standard Snellen visual quality.…”

Correlation between visual acuity and interface reflectivity measured by pentacam following DSAEK

“…Nielsen and Hjortdal measured BSCVA and contrast sensitivity in patients following DSAEK who had untreated Fuchs' endothelial dystrophy in the fellow eye. In a patient's questionnaire, they found an explicit preference of the DSAEK eye most likely due to improved contrast sensitivity as BSCVA nearly was the same in both eyes (Nielsen & Hjortdal 2011). But, nevertheless, improvement of BSCVA contributes to patient's satisfaction and is a main purpose in treating endothelial diseases.…”

Relationship of Visual Acuity and Lamellar Thickness in Descemet Stripping Automated Endothelial Keratoplasty

“…5, 6 In patients with Fuchs dystrophy, even when visual acuity is controlled for by statistical methods, there is an improved contrast sensitivity in eyes that have undergone DSAEK as compared with those that have not had surgery. 7,8 Despite the improvement in vision compared with Fuchs dystrophy, a meta-analysis performed by the American Academy of Ophthalmology demonstrated that best-corrected visual acuity (BCVA) in eyes after DSAEK is sometimes limited as compared with a patient's expected potential vision. For DSAEK eyes, the average BCVA ranged from 20/34 to 20/66 with a mean length of follow-up of 9 months (range, 3-21 months).…”